• Title/Summary/Keyword: Community composition

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Effects of Quorum Quenching on the Microbial Community of Biofilm in an Anoxic/Oxic MBR for Wastewater Treatment

  • Jo, Sung Jun;Kwon, Hyeokpil;Jeong, So-Yeon;Lee, Sang Hyun;Oh, Hyun-Suk;Yi, Taewoo;Lee, Chung-Hak;Kim, Tae Gwan
    • Journal of Microbiology and Biotechnology
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    • v.26 no.9
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    • pp.1593-1604
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    • 2016
  • Recently, bacterial quorum quenching (QQ) has been proven to have potential as an innovative approach for biofouling control in membrane bioreactors (MBRs) for advanced wastewater treatment. Although information regarding the microbial community is crucial for the development of QQ strategies, little information exists on the microbial ecology in QQ-MBRs. In this study, the microbial communities of biofilm were investigated in relation to the effect of QQ on anoxic/oxic MBRs. Two laboratory-scale MBRs were operated with and without QQ-beads (QQ-bacteria entrapped in beads). The transmembrane pressure increase in the QQ-MBRs was delayed by approximately 100-110% compared with conventional- and vacant-MBRs (beads without QQ-bacteria) at 45 kPa. In terms of the microbial community, QQ gradually favored the development of a diverse and even community. QQ had an effect on both the bacterial composition and change rate of the bacterial composition. Proteobacteria and Bacteroidetes were the most dominant phyla in the biofilm, and the average relative composition of Proteobacteria was low in the QQ-MBR. Thiothrix sp. was the dominant bacterium in the biofilm. The relative composition of Thiothrix sp. was low in the QQ-MBR. These findings provide useful information that can inform the development of a new QQ strategy.

The Effects of Group Walking Exercise Program on Body Composition, Blood Lipids and Psychological Factors (집단 걷기운동이 여성의 체성분, 혈중지질 및 심리적인 요인에 미치는 효과)

  • Ko, Young-Aie;Hwang, In-Young;Baek, Hee-Chong
    • Research in Community and Public Health Nursing
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    • v.17 no.1
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    • pp.38-45
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    • 2006
  • Purpose: The purpose of this study was to examine the effects of a group walking exercise program on body composition, blood lipids and psychological factors at a community. Method: The subjects were 200 women(29 groups) who agreed to participate in group walking exercise for three months. Their ages ranged between 30 to 77 years. A simple walking exercise protocol was given to the participants, which was to do walking over three times a week and over thirty minutes each time. We compared the participants' body composition (BMI, PBF, BFM, FFM, WHR and VFA), blood lipids (HDL C, LDL C, total cholesterol, triglyceride) and exercise-self efficacy, self esteem, and quality of life before and after group walking. Collected data were analyzed through paired t test using the SAS program. Results: BMI. PBF, BFM, WHR, and VFA were significantly reduced (p<.01). However. FFM did not increase significantly (p=.416). There were significant changes in TC and TG (p<.01) but not in LDL C (P=.340). HDL C decreased but within the normal range. Exercise-self efficacy and quality of life did not increase significantly. Only self esteem increased significantly (p<.0001). Conclusion: Group walking exercise had positive effects on body composition, blood lipid and self esteem in community women.

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Progressive Succession and Potential Natural Vegetation on the Forest Vegetation in and surrounding Daegu, Korea (대구 인접 지역 삼림식생의 진행천이와 잠재자연식생)

  • Choung, Heung-Lak;Chun, Young-Moon;Lee, Ho-Joon
    • Journal of Ecology and Environment
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    • v.29 no.3
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    • pp.265-275
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    • 2006
  • This study represents the mechanism of progressive succession and potential natural vegetation on the forest vegetation in and surrounding Daegu. As a result of DCA, the feature of community was determined by an altitude and humid gradients. The soil moisture, contents of organic matter and total nitrogen increased as the community developed. In the interspecific association analysis, the forest vegetation was divided into two species groups and they were influenced by temperature and soil moisture. Especially, each two groups showed different stages of vegetation development according to the progressive succession and life form composition supported those results. It was predicted that Quercus variabilis, Q. acutissima, Q. dentata and Pinus densiflora communities would develop into Q. serrata community or Q. mongolica community depending on their location or species composition. In the study area, the potential natural vegetation was divided into 3 communities by biogeographical gradients such as species composition, soil environment, and geographical features: 1)Q. mongolica community in the middle-upper area of the mountain, 2)Q. serrata community in the middle-lower area of the mountain and 3)Carpinus cordata-Acer mono community in the cove area. It is suggested that the Q.mongolica and C.cordata-A.mono communities become actual vegetation and potential natural vegetation. But it is also suggested that the P. densiflora community would be changed into the potential natural vegetation of the Q. mongolica community and Q. serrata community on the basis of the present species composition.

Density Composition and Feeding Guild of the Dominant Polychaetous Community in Shallow Muddy Bottom in Tomioka Bay, Amakusa, Japan

  • LEE Si-Wan;PAIK Eui-In
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.28 no.6
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    • pp.793-804
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    • 1995
  • Polychaetous community survey in Tomioka Bay was carried out 5 times seasonally from May 1991 to March 1992 by quantitative grab sampling (0.05m2) at 11 stations. Based on the granulometric composition and environmental factors, a homogeneous soft bottom was found in St.5-10. The species of the polychaete were classified into three feeding groups using the Fauchald and Jumars' feeding guild system. According to polychaetous community composition data, deposit feeders predominate in sandy silt area where the silt-clay content is $60-69.3\%.$ These deposit feeders were subdivided into surface deposit feeders and subsurface deposit feeders by their living position and mode. Also, suspension feeding group comes as the third dominant group. Seasonal changes of each feeding group were described in terms of numerical density and biomass. Feeding layer and types of dominant species (Lumbrineris longifolia: surface deposit feeder; Praxillella pacifica: subsurface deposit feeder; Chone duneri; suspension filter feeder, etc.) were examined in the intact sediment core samples. Also, longterm density change among the three dominant species during 10 years was disussed.

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A Study on the Composition and Characteristic of Coworking Space (코워킹 공간구성과 특성에 관한 연구)

  • Han, Hye-Sun
    • Korean Institute of Interior Design Journal
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    • v.22 no.5
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    • pp.276-283
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    • 2013
  • Coworking space is the ideal concept of small companies, freelancers, startups, and entrepreneurs operating out of a shared office space while working independently of one another. The coworkers share the core values of coworking: collaboration, openness, accessibility, sustainability, and community. Little academic research has been completed on the composition of coworking spaces and the businesses that use them. The purpose of this study is to examine the organization and characteristic of coworking space based on domestic and international cases for providing basic data on the coworking space plan. This study examined existing academic literature, media, online sources to assess the environmental background of worldwide coworking space, the current status, conceptualization, and membership plan that can be appled coworking spaces. The case study for coworking space is limited to the space where there is web site that is showed floor plan. Coworking spaces are designed to be environmentally friendly, offering common area with many facilities to encouraging community and collaboration. For creating ideal coworking space, the concept of coworking space must be recognized as a community space for interaction and creativity between people and space. Based on the result of this study, the appropriate zoning, circulation and specific floor plan of coworking space is needed for the next research.

Composition and Structure of Macrofouling Communities on Ocean-going Ships in the Far East Sea Basin

  • Moshchenko, Alexander V.;Zvyagintsev, Alexander Y.
    • Ocean and Polar Research
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    • v.23 no.2
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    • pp.63-75
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    • 2001
  • Species composition and community structure of the fouling found on the hulls of 28 ships traveling through 6 main shipping routes (SR)in the Far East Sea Basin were analyzed using statistical methods. Samples obtained during 1976-1990 expeditions of the Institute of Marine Biology were used for the analyses. These samples were taken from the ships anchored in the harbor by SCUBA diving and in dry-docks of the Vladivostok ship-repairing yard. Similar composition of the fouling communities occurred on the ships travelling the same SR. In five cases, fouling was dominated by different Cirripedia communities. And, in one case, a community of the mussel Mytilus trossulus was found. In most cases the results of the factor analyses showed extremely low level of the relationships among different animals and algal species in fouling communities. Each ocean-going ship had an original structure of the fouling. Spatially disconnected animal associations of tropical and boreal origin may simultaneously coexist at the same ship. This paper testified to the originality of the zone of anthropogenic substrata as a benthos concentrator in the pelagic regions of the world ocean. The fouling from different zones showed that each zone possesses peculiar features and regularities of the composition and relationships between organisms dwelling here.

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Effects of Aquarobic Exercise on Body Composition and Cardiovascular Index in Elderly Women

  • KIM, Chankyu;LEE, Byunghoon
    • Physical Therapy Rehabilitation Science
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    • v.10 no.3
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    • pp.320-327
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    • 2021
  • Objective: The community has implemented a variety of exercise programs for the elderly population. However, studies comparing changes in the cardiovascular system through body composition and blood analysis after applying aqua aerobic exercise are insufficient. The purpose of this study was to investigate the effect of a 12 weeks aqua exercise on body composition and cardiovascular index in elderly women. Design: Non-equivalence pre-post design. Methods: Thirty elderly women were assigned to aquarobic group(n=15) and control group(n=15). The aquarobic exercise was 60 minutes per every session, 2times per week, for 12weeks. Weight, skeletal muscle mass, body fat percentage, total cholesterol, triglyceride, HDL cholesterol, and LDL cholesterol were measured before and after the exercise program. Paired and independent t-tests were performed using SPSS program. Results: The result showed was weight(p<0.05), body fat percentage(p<0.05), total cholesterol(p<0.05), triglyceride(p<0.05), HDL cholesterol(p<0.05), and LDL cholesterol(p<0.05) were significantly decreased and skeletal muscle mass(p>0.05) was not significantly increased after aquatic exercise program. Conclusions: According to the study result, aqua exercise program made a positive effect in the improvement of obesity and cardiovascular function in elderly women. Therefore, we suggest that you actively consider implementing the Aquarobic exercise program when operating the community health promotion program in the future. In addition, in future studies, comparative studies according to various ages and genders and studies on the effects of aqua aerobic exercise as a community exercise program for chronically illness patients are needed.

Minimal Areas and Community Structures of Pinus densiflora Forests and Quercus mongolica Forests (소나무림 및 신갈나무림의 최소면적과 군락구조)

  • Kim, Jong-Woon;Deuk-Im Lee;Woen Kim
    • The Korean Journal of Ecology
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    • v.18 no.4
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    • pp.451-462
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    • 1995
  • A comparative study on the minimal areas and the community structures in pine IPinus densiflora) and oak (Quercus mongolica) frests was carried out. Basic tools used in the present study were species diversity and classical ayntaxonomy (Z.-M. School) of the phytocoenosis. Total 120 nest-quadrats in 40 stands situated at the syngeographical region of the Lindero-Quercion mongolicae were investigated. Each stand was classified on the basis of species combination, and species abundance was computed with net contribution degree (NCD). Composition ratio of plant-from and rate of actual species diversity (ASD) to syntaxa were computed for better interpretation of the minimal areas. Four syntaxa were structured: Saso-Quercetum mongolicae, Viola albida-Quercus mongolica community, Carex hummilis-Pinus densiflora community and Juniperus rigida-Pinus densiflora community. Their minimal areas were determined as 305, 196, 169, and 81 ㎡, respectively. Aconsistent regularity between species composition ratio and community structure in the multi-layered plant community was hardly found. The minimal areas increased linearly with increasing rate of ASD, and a phytocoenosis developed by diverse arboreta in the understory and shrub-layer should be investigated with larger sampling sizes.

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Influence of Allyl Isothiocyanate on the Soil Microbial Community Structure and Composition during Pepper Cultivation

  • Gao, Jingxia;Pei, Hongxia;Xie, Hua
    • Journal of Microbiology and Biotechnology
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    • v.31 no.7
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    • pp.978-989
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    • 2021
  • Allyl isothiocyanate (AITC), as a fumigant, plays an important role in soil control of nematodes, soil-borne pathogens, and weeds, but its effects on soil microorganisms are unclear. In this study, the effects of AITC on microbial diversity and community composition of Capsicum annuum L. soil were investigated through Illumina high-throughput sequencing. The results showed that microbial diversity and community structure were significantly influenced by AITC. AITC reduced the diversity of soil bacteria, stimulated the diversity of the soil fungal community, and significantly changed the structure of fungal community. AITC decreased the relative abundance of dominant bacteria Planctomycetes, Acinetobacter, Pseudodeganella, and RB41, but increased that of Lysobacter, Sphingomonas, Pseudomonas, Luteimonas, Pseudoxanthomonas, and Bacillus at the genera level, while for fungi, Trichoderma, Neurospora, and Lasiodiplodia decreased significantly and Aspergillus, Cladosporium, Fusarium, Penicillium, and Saccharomyces were higher than the control. The correlation analysis suggested cellulase had a significant correlation with fungal operational taxonomic units and there was a significant correlation between cellulase and fungal diversity, while catalase, cellulose, sucrase, and urease were the major contributors in the shift of the community structure. Our results will provide useful information for the use of AITC in the assessment of environmental and ecological security.

The Effects of Walking on the Physical Health of Residents in Rural Areas (걷기운동 프로그램이 농촌주민의 신체적 건강에 미치는 효과)

  • Kim, Chun-Mi
    • Research in Community and Public Health Nursing
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    • v.19 no.3
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    • pp.349-357
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    • 2008
  • Purpose: The Purpose of this study was to analyze the effect of walking on physical health such as body composition, blood pressure, blood glucose and blood lipids for residents in rural areas. Method: Data were collected from 109 residents at 4 community health centers and during the 12 weeks' period between May and July, 2007 with quasi-experimental pre/post-test design. The data were processed with SPSS Win 12.0. Result: 69.5% of the subjects had chronic degenerative diseases such as hypertension, arthritis and diabetes mellitus. Also, 52.9% had overweight and 14.7% had excessive obesity. There were significant positive changes in BMI, blood pressure, blood glucose and LDL among obese residents. However, there was no significant difference in total cholesterol, triglycerides and HDL among blood lipids. Conclusion: This study showed that a 3 months' walking program had positive effects on physical health and it should be continued.

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